If Brexit is about "taking back control" it is also going to be about losing influence in business terms as well as political. I don't think that many Japanese companies are going to 100% leave the UK, but most have already put in place ways to skirt around Brexit UK. 1/

There are 200 or so Japanese companies in the UK which give figures for their exports to the EU from the UK. About half are manufacturing in UK. Employing around 56,000 people, £45bn turnover. 2/

Japanese businesses are famously long term in view, cash rich, resilient, risk averse, so they have been throwing money at Brexit solutions for some years now. Many have set up warehousing in the EU + importing directly there rather than via UK 3/

+/or have turned their UK subsidiaries into branches of their EU subsidiaries +/or transferred EU customer accounts to EU subsidiaries. So revenue for UK will be management fees/commissions rather than sales. Not so much profit to tax. 4/

Some have shut down their UK subsidiaries entirely - and/or started plants in Eastern Europe. It looks like preparations are being made for more UK manufacturing to shut down if necessary. Japanese electronics manufacturers mostly shut down in UK in 2000s after all. 5/

Result may be not that many UK jobs lost or Japanese product filled lorry jams, but will be a loss of tax revenue, capital and as I said in the first tweet, influence of UK in the region. British are going to have to shout more loudly when speaking to foreigners than usual. 6/